1/2in Dia Reduced Shank HSS <span class="ui-risk_flag3"><span class="ui-risk_flag3"><span class="ui-risk_flag3">Twist</span></span></span> Drill Bit Milling Cutter 21mm Features: Forged from premium 9341 steel, high hardness and good wear resistance. The drilling head is processed by quenching to ensure excellent performance. 135°drill point adopts double relief angle design to achieve incisive cutting. 38°large spiral angle design increases cutting chip flute. Standard 1/2 inch round shank for convenient and secure use. Good reliability, perfectly fit for cutting wood, metal and etc. Specifications: Condition: Material: 9341 steel Color: Shown as picture Shank Diameter: 1/2in Optional Drilling Diameter: 16mm, 17mm, 20mm, 21mm Package Weight: Approx.138g(16mm), 156g(17mm), 189g(20mm), 215g(21mm) Package List: 1 * Twist Drill Bit Note:Please note that the new type and old type of this product will be sent randomly, and make sure you will not mind before ordering.